Cisco AJ732A - MDS 9134 Fabric Switch Release Note page 11

CISCO MDS 9000 N-PORT VIRTUALIZATION (NPV) MODE
N-Port Virtualization (NPV) Mode is a software feature that can be optionally enabled on the C-
series MDS 9124 and the MDS 9124e Fabric Switches running SAN-OS 3.2(1a) or newer.
Switches operating in NPV mode do not join a fabric; rather, they pass traffic between NPV core
switch links and end devices.
NPV technology addresses the increase in the number of domain IDs needed to deploy a large
number of ports by making the MDS 9124 and the MDS 9124e behave as a host to the core FC
switch. NPV aggregates multiple locally connected N-ports into one or more external NP link(s),
which share the domain ID of the NPV core switch. NPV also allows multiple devices to attach
to the same port on the NPV core switch, thereby reducing the need for more ports on the core
switch. NPV makes use of N-port ID virtualization (NPIV) to receive multiple FCIDs allocated
from the core switch on the NP port. Refer to the Cisco MDS 9000 Family Configuration Guide
for instructions on how to configure NPV.
In addition to being supported in Cisco fabrics, NPV is supported for connectivity to B-Series and
M-Series fabrics. Refer to the hp StorageWorks Fabric Interoperability: Merging Fabrics Based
on C-series and B-Series Fibre Channel Switches and hp StorageWorks Fabric Interoperability:
Merging Fabric Based on C-series and M-Series Fibre Channel Switches for specific supported
B-Series and M-Series software versions.
CISCO MDS 9000 FLEXATTACH
FlexAttach is supported on the Cisco Fabric Switch for HP c-Class BladeSystem, the Cisco MDS
9124 switch, and the Cisco MDS 9134 switch, when NPV mode is enabled. The FlexAttach
feature reduces the time and coordination effort required by SAN and server administrators when
installing and replacing servers. The use of FlexAttach alleviates the need for re-zoning and LUN
reconfiguration changes when a new server is installed or when an existing server needs
replacement. For information on FlexAttach, refer to the Configuring FlexAttach Virtual pWWN
chapter in the Cisco MDS 9000 Family Configuration Guide.
Administrators can benefit from FlexAttach in the following scenarios:

Pre-configuration—Pre-configure the SAN for the addition of new servers where
physical WWPNs are unknown, using the virtual WWPNs during an existing
maintenance window. Once the servers are available, they can be plugged into the fabric
without requiring any SAN configuration changes.

Replacement (new server)—Replace a server in an existing server port without SAN
configuration changes since FlexAttach assigns a virtual WWPN to the server port.

Replacement (spare) —Bring the spare server online without SAN configuration changes.
This is achieved by moving the virtual WWPN from the current server port to the spare
port.

Server Mobility —Move the server to a different NPV switch (within the same fabric or
VSAN) without SAN configuration changes. FlexAttach allows manual creation and
transfer of virtual WWPNs from one server port to another
11 MDS Multilayer Director & Multilayer Fabric Switches Release Notes
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